Deformation analysis of shallow tunneling with unconsolidated soil using nonlinear numerical modeling

비선형 수치모델링을 이용한 미고결 지반 저토피 터널의 변형해석

  • Received : 2009.04.01
  • Accepted : 2010.03.08
  • Published : 2010.03.31

Abstract

The estimation of surface settlement, ground behavior and tunnel displacement are the main factors in urban tunnel design with shallow depth and unconsolidated soil. On deformation analysis of shallow tunnel, it is important to identify possible deformation mechanism of shear bands developing from tunnel shoulder to the ground surface. This paper investigated the effects of key design parameter affecting deformation behavior by numerical analysis using nonlinear model incorporating the reduction of shear stiffness and strength parameters with the increment of the maximum shear strain after the initiation of plastic yielding. Numerical parametric studies are carried out to consider the reduction of shear stiffness and strength parameters, horizontal stress ratio, cohesion and shotcrete thickness.

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